The goal of this project is to evaluate feasibility and systemic exposure following short-term administration of crumb rubber by various exposure scenarios (gavage, drinking water, feed, inhalation and dermal). These studies are in the design phase. Over 11,000 synthetic turf fields exist in the U.S., with approximately 1,200 being added annually. The component of turf that is of most concern is crumb rubber infill, made from recycled automotive tires. Crumb rubber contains numerous potential carcinogenic and toxic substances, yet the exposure of people playing on installed fields to these hazardous components is not well understood. Information gained from NTP toxicology studies will provide public health agencies with information to inform exposure and health assessments. It is anticipated that there will be significant challenges, surrounding exposure that must be addressed prior to initiating such studies. In addition to informing feasibility of conduct of future NTP toxicity studies and provide information on systemic exposure by various routes, these data will aid other researchers design toxicity studies and interpret the resulting data. Keywords: toxicity, crumb rubber, systemic exposure, turf.